Step-by-step explanation: |x − y| = 1, ok lets play as Alice, my number is y, and the bob number is x.
the condition says that x-y = 1 or x-y = -1.
so, if you know x, then y = 1 +y or y = y - 1. so you have two possibilities.
let's see two cases : first, let's suppose there are no code in the conversation. Then the only way of being shure of your number, is if one of them have the lowest positive number, so the other should have the next one. So if Bob have the number one, Alice knows for shure that she has the 2. Bob knows that she has a 2, but that means he could have a 1 or a 3, but when he sees that Alice is shure about her number, he knows that his number is the 1.
the second case is where the conversation may be a sort of code, saying a phrase x times and changing when x = the number of the other person, in this case, bob will have the 201 and alice the 202.
Answer:
415/619
Step-by-step explanation:
619 is a prime number, so the fraction is in simplest form already.
Answer: TRUE!
Variables ARE letters used in place of numbers absolutely
B is true.
I think E is also true.
